[PATCH v1 0/3] drm/bridge: lt8912b: Add power supplies

[PATCH v1 0/3] drm/bridge: lt8912b: Add power supplies

[Francesco Dolcini]

From: Francesco Dolcini <francesco.dolcini@toradex.com>

Add support for suspend and resume, power off the bridge when going into
suspend and power on when resuming.

Stefan Eichenberger (3):
  drm/bridge: lt8912b: Add suspend/resume support
  dt-bindings: display: bridge: lt8912b: Add power supplies
  drm/bridge: lt8912b: Add power supplies

 .../display/bridge/lontium,lt8912b.yaml       | 21 +++++++
 drivers/gpu/drm/bridge/lontium-lt8912b.c      | 58 +++++++++++++++++++
 2 files changed, 79 insertions(+)

-- 
2.25.1

[PATCH v1 1/3] drm/bridge: lt8912b: Add suspend/resume support

[Francesco Dolcini]

From: Stefan Eichenberger <stefan.eichenberger@toradex.com>

Add support for suspend and resume. The lt8912b will power off when
going into suspend and power on when resuming.

Signed-off-by: Stefan Eichenberger <stefan.eichenberger@toradex.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
---
 drivers/gpu/drm/bridge/lontium-lt8912b.c | 28 ++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/drivers/gpu/drm/bridge/lontium-lt8912b.c b/drivers/gpu/drm/bridge/lontium-lt8912b.c
index 03532efb893b..097ab04234b7 100644
--- a/drivers/gpu/drm/bridge/lontium-lt8912b.c
+++ b/drivers/gpu/drm/bridge/lontium-lt8912b.c
@@ -634,6 +634,33 @@ static const struct drm_bridge_funcs lt8912_bridge_funcs = {
 	.get_edid = lt8912_bridge_get_edid,
 };
 
+static int lt8912_bridge_resume(struct device *dev)
+{
+	struct lt8912 *lt = dev_get_drvdata(dev);
+	int ret;
+
+	ret = lt8912_hard_power_on(lt);
+	if (ret)
+		return ret;
+
+	ret = lt8912_soft_power_on(lt);
+	if (ret)
+		return ret;
+
+	return lt8912_video_on(lt);
+}
+
+static int lt8912_bridge_suspend(struct device *dev)
+{
+	struct lt8912 *lt = dev_get_drvdata(dev);
+
+	lt8912_hard_power_off(lt);
+
+	return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(lt8912_bridge_pm_ops, lt8912_bridge_suspend, lt8912_bridge_resume);
+
 static int lt8912_parse_dt(struct lt8912 *lt)
 {
 	struct gpio_desc *gp_reset;
@@ -770,6 +797,7 @@ static struct i2c_driver lt8912_i2c_driver = {
 	.driver = {
 		.name = "lt8912",
 		.of_match_table = lt8912_dt_match,
+		.pm = pm_sleep_ptr(&lt8912_bridge_pm_ops),
 	},
 	.probe = lt8912_probe,
 	.remove = lt8912_remove,
-- 
2.25.1

Re: [PATCH v1 1/3] drm/bridge: lt8912b: Add suspend/resume support

[Robert Foss]

On Wed, Nov 15, 2023 at 1:14 PM Francesco Dolcini <francesco@dolcini.it> wrote:
>
> From: Stefan Eichenberger <stefan.eichenberger@toradex.com>
>
> Add support for suspend and resume. The lt8912b will power off when
> going into suspend and power on when resuming.
>
> Signed-off-by: Stefan Eichenberger <stefan.eichenberger@toradex.com>
> Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
> ---
>  drivers/gpu/drm/bridge/lontium-lt8912b.c | 28 ++++++++++++++++++++++++
>  1 file changed, 28 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/lontium-lt8912b.c b/drivers/gpu/drm/bridge/lontium-lt8912b.c
> index 03532efb893b..097ab04234b7 100644
> --- a/drivers/gpu/drm/bridge/lontium-lt8912b.c
> +++ b/drivers/gpu/drm/bridge/lontium-lt8912b.c
> @@ -634,6 +634,33 @@ static const struct drm_bridge_funcs lt8912_bridge_funcs = {
>         .get_edid = lt8912_bridge_get_edid,
>  };
>
> +static int lt8912_bridge_resume(struct device *dev)
> +{
> +       struct lt8912 *lt = dev_get_drvdata(dev);
> +       int ret;
> +
> +       ret = lt8912_hard_power_on(lt);
> +       if (ret)
> +               return ret;
> +
> +       ret = lt8912_soft_power_on(lt);
> +       if (ret)
> +               return ret;
> +
> +       return lt8912_video_on(lt);
> +}
> +
> +static int lt8912_bridge_suspend(struct device *dev)
> +{
> +       struct lt8912 *lt = dev_get_drvdata(dev);
> +
> +       lt8912_hard_power_off(lt);
> +
> +       return 0;
> +}
> +
> +static DEFINE_SIMPLE_DEV_PM_OPS(lt8912_bridge_pm_ops, lt8912_bridge_suspend, lt8912_bridge_resume);
> +
>  static int lt8912_parse_dt(struct lt8912 *lt)
>  {
>         struct gpio_desc *gp_reset;
> @@ -770,6 +797,7 @@ static struct i2c_driver lt8912_i2c_driver = {
>         .driver = {
>                 .name = "lt8912",
>                 .of_match_table = lt8912_dt_match,
> +               .pm = pm_sleep_ptr(&lt8912_bridge_pm_ops),
>         },
>         .probe = lt8912_probe,
>         .remove = lt8912_remove,
> --
> 2.25.1
>

Reviewed-by: Robert Foss <rfoss@kernel.org>

[PATCH v1 2/3] dt-bindings: display: bridge: lt8912b: Add power supplies

[Francesco Dolcini]

From: Stefan Eichenberger <stefan.eichenberger@toradex.com>

Add Lontium lt8912b power supplies.

Signed-off-by: Stefan Eichenberger <stefan.eichenberger@toradex.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
---
 .../display/bridge/lontium,lt8912b.yaml       | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml
index f201ae4af4fb..2cef25215798 100644
--- a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml
+++ b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml
@@ -55,6 +55,27 @@ properties:
       - port@0
       - port@1
 
+  vcchdmipll-supply:
+    description: A 1.8V supply that powers the HDMI PLL.
+
+  vcchdmitx-supply:
+    description: A 1.8V supply that powers the HDMI TX part.
+
+  vcclvdspll-supply:
+    description: A 1.8V supply that powers the LVDS PLL.
+
+  vcclvdstx-supply:
+    description: A 1.8V supply that powers the LVDS TX part.
+
+  vccmipirx-supply:
+    description: A 1.8V supply that powers the MIPI RX part.
+
+  vccsysclk-supply:
+    description: A 1.8V supply that powers the SYSCLK.
+
+  vdd-supply:
+    description: A 1.8V supply that powers the digital part.
+
 required:
   - compatible
   - reg
-- 
2.25.1

Re: [PATCH v1 2/3] dt-bindings: display: bridge: lt8912b: Add power supplies

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 1659 bytes --]

On Wed, Nov 15, 2023 at 01:13:37PM +0100, Francesco Dolcini wrote:
> From: Stefan Eichenberger <stefan.eichenberger@toradex.com>
> 
> Add Lontium lt8912b power supplies.
> 
> Signed-off-by: Stefan Eichenberger <stefan.eichenberger@toradex.com>
> Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>

Acked-by: Conor Dooley <conor.dooley@microchip.com>

Cheers,
Conor,

> ---
>  .../display/bridge/lontium,lt8912b.yaml       | 21 +++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml
> index f201ae4af4fb..2cef25215798 100644
> --- a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml
> +++ b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml
> @@ -55,6 +55,27 @@ properties:
>        - port@0
>        - port@1
>  
> +  vcchdmipll-supply:
> +    description: A 1.8V supply that powers the HDMI PLL.
> +
> +  vcchdmitx-supply:
> +    description: A 1.8V supply that powers the HDMI TX part.
> +
> +  vcclvdspll-supply:
> +    description: A 1.8V supply that powers the LVDS PLL.
> +
> +  vcclvdstx-supply:
> +    description: A 1.8V supply that powers the LVDS TX part.
> +
> +  vccmipirx-supply:
> +    description: A 1.8V supply that powers the MIPI RX part.
> +
> +  vccsysclk-supply:
> +    description: A 1.8V supply that powers the SYSCLK.
> +
> +  vdd-supply:
> +    description: A 1.8V supply that powers the digital part.
> +
>  required:
>    - compatible
>    - reg
> -- 
> 2.25.1
> 

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

[PATCH v1 3/3] drm/bridge: lt8912b: Add power supplies

[Francesco Dolcini]

From: Stefan Eichenberger <stefan.eichenberger@toradex.com>

Add supplies to the driver that can be used to turn the Lontium lt8912b
on and off. It can have up to 7 independent supplies, we add them all
and enable/disable them with bulk_enable/disable.

Signed-off-by: Stefan Eichenberger <stefan.eichenberger@toradex.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
---
 drivers/gpu/drm/bridge/lontium-lt8912b.c | 30 ++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/drivers/gpu/drm/bridge/lontium-lt8912b.c b/drivers/gpu/drm/bridge/lontium-lt8912b.c
index 097ab04234b7..273157428c82 100644
--- a/drivers/gpu/drm/bridge/lontium-lt8912b.c
+++ b/drivers/gpu/drm/bridge/lontium-lt8912b.c
@@ -43,6 +43,8 @@ struct lt8912 {
 
 	struct videomode mode;
 
+	struct regulator_bulk_data supplies[7];
+
 	u8 data_lanes;
 	bool is_power_on;
 };
@@ -257,6 +259,12 @@ static int lt8912_free_i2c(struct lt8912 *lt)
 
 static int lt8912_hard_power_on(struct lt8912 *lt)
 {
+	int ret;
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(lt->supplies), lt->supplies);
+	if (ret)
+		return ret;
+
 	gpiod_set_value_cansleep(lt->gp_reset, 0);
 	msleep(20);
 
@@ -267,6 +275,9 @@ static void lt8912_hard_power_off(struct lt8912 *lt)
 {
 	gpiod_set_value_cansleep(lt->gp_reset, 1);
 	msleep(20);
+
+	regulator_bulk_disable(ARRAY_SIZE(lt->supplies), lt->supplies);
+
 	lt->is_power_on = false;
 }
 
@@ -661,6 +672,21 @@ static int lt8912_bridge_suspend(struct device *dev)
 
 static DEFINE_SIMPLE_DEV_PM_OPS(lt8912_bridge_pm_ops, lt8912_bridge_suspend, lt8912_bridge_resume);
 
+static int lt8912_get_regulators(struct lt8912 *lt)
+{
+	unsigned int i;
+	const char * const supply_names[] = {
+		"vdd", "vccmipirx", "vccsysclk", "vcclvdstx",
+		"vcchdmitx", "vcclvdspll", "vcchdmipll"
+	};
+
+	for (i = 0; i < ARRAY_SIZE(lt->supplies); i++)
+		lt->supplies[i].supply = supply_names[i];
+
+	return devm_regulator_bulk_get(lt->dev, ARRAY_SIZE(lt->supplies),
+				       lt->supplies);
+}
+
 static int lt8912_parse_dt(struct lt8912 *lt)
 {
 	struct gpio_desc *gp_reset;
@@ -712,6 +738,10 @@ static int lt8912_parse_dt(struct lt8912 *lt)
 		goto err_free_host_node;
 	}
 
+	ret = lt8912_get_regulators(lt);
+	if (ret)
+		goto err_free_host_node;
+
 	of_node_put(port_node);
 	return 0;
 
-- 
2.25.1

Re: [PATCH v1 3/3] drm/bridge: lt8912b: Add power supplies

[Robert Foss]

On Wed, Nov 15, 2023 at 1:14 PM Francesco Dolcini <francesco@dolcini.it> wrote:
>
> From: Stefan Eichenberger <stefan.eichenberger@toradex.com>
>
> Add supplies to the driver that can be used to turn the Lontium lt8912b
> on and off. It can have up to 7 independent supplies, we add them all
> and enable/disable them with bulk_enable/disable.
>
> Signed-off-by: Stefan Eichenberger <stefan.eichenberger@toradex.com>
> Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
> ---
>  drivers/gpu/drm/bridge/lontium-lt8912b.c | 30 ++++++++++++++++++++++++
>  1 file changed, 30 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/lontium-lt8912b.c b/drivers/gpu/drm/bridge/lontium-lt8912b.c
> index 097ab04234b7..273157428c82 100644
> --- a/drivers/gpu/drm/bridge/lontium-lt8912b.c
> +++ b/drivers/gpu/drm/bridge/lontium-lt8912b.c
> @@ -43,6 +43,8 @@ struct lt8912 {
>
>         struct videomode mode;
>
> +       struct regulator_bulk_data supplies[7];
> +
>         u8 data_lanes;
>         bool is_power_on;
>  };
> @@ -257,6 +259,12 @@ static int lt8912_free_i2c(struct lt8912 *lt)
>
>  static int lt8912_hard_power_on(struct lt8912 *lt)
>  {
> +       int ret;
> +
> +       ret = regulator_bulk_enable(ARRAY_SIZE(lt->supplies), lt->supplies);
> +       if (ret)
> +               return ret;
> +
>         gpiod_set_value_cansleep(lt->gp_reset, 0);
>         msleep(20);
>
> @@ -267,6 +275,9 @@ static void lt8912_hard_power_off(struct lt8912 *lt)
>  {
>         gpiod_set_value_cansleep(lt->gp_reset, 1);
>         msleep(20);
> +
> +       regulator_bulk_disable(ARRAY_SIZE(lt->supplies), lt->supplies);
> +
>         lt->is_power_on = false;
>  }
>
> @@ -661,6 +672,21 @@ static int lt8912_bridge_suspend(struct device *dev)
>
>  static DEFINE_SIMPLE_DEV_PM_OPS(lt8912_bridge_pm_ops, lt8912_bridge_suspend, lt8912_bridge_resume);
>
> +static int lt8912_get_regulators(struct lt8912 *lt)
> +{
> +       unsigned int i;
> +       const char * const supply_names[] = {
> +               "vdd", "vccmipirx", "vccsysclk", "vcclvdstx",
> +               "vcchdmitx", "vcclvdspll", "vcchdmipll"
> +       };
> +
> +       for (i = 0; i < ARRAY_SIZE(lt->supplies); i++)
> +               lt->supplies[i].supply = supply_names[i];
> +
> +       return devm_regulator_bulk_get(lt->dev, ARRAY_SIZE(lt->supplies),
> +                                      lt->supplies);
> +}
> +
>  static int lt8912_parse_dt(struct lt8912 *lt)
>  {
>         struct gpio_desc *gp_reset;
> @@ -712,6 +738,10 @@ static int lt8912_parse_dt(struct lt8912 *lt)
>                 goto err_free_host_node;
>         }
>
> +       ret = lt8912_get_regulators(lt);
> +       if (ret)
> +               goto err_free_host_node;
> +
>         of_node_put(port_node);
>         return 0;
>
> --
> 2.25.1
>

Reviewed-by: Robert Foss <rfoss@kernel.org>